Abstract: Apparatus for applying torsional vibration to a rotating machine is provided. In one exemplary embodiment the apparatus includes a permanent magnet machine (12) connected to the rotating machine (22) and configured to generate a three-phase AC output voltage. A converter (36) may be coupled to receive the three-phase AC output voltage from the permanent magnet machine to supply a DC load current. An electrical load (44) (or exciter) may be coupled to the converter to receive the load current. An oscillator (42) is connected to the converter to provide an oscillation signal for modulating the load current from the converter. Modulated load current causes variable loading of the permanent magnet machine thereby creating an oscillatory torque in the permanent magnet machine (12). The oscillatory torque causes torsional vibration in the rotating machine. Various components of the apparatus for applying torsional vibration may be part of a field-deployed power generating system.

Abstract: A knock sensor of the invention includes a base having a cylindrical part mounted on a vibration generating part and a flange part, an annular piezoelectric element fitted to the cylindrical part and for converting a knocking vibration of the vibration generating part into an electric signal to detect it, electrodes respectively provided to be in contact with both surfaces of the piezoelectric element, terminal plates disposed to be in contact with the respective electrodes and for extracting an output of the piezoelectric element to outside, and a hold unit for pressure holding the piezoelectric element, the electrodes and the terminal plates to the flange part, in which a conductive adhesive material having an almost equal thickness to the electrode is provided on a portion of the piezoelectric element which is not in contact with the electrode.

Abstract: The present invention relates to a failure detecting system that enables the detection of a break in a rail and the like by a simple network configuration. Detecting units (20 and 50), relay units (30A, 30B, 60A through 60C) and terminal units (40 and 70) are arranged along rails (11, 11A and 11B). Using the rails (11, 11A and 11B) as transmission media, ultrasonic waves transmitted from the detecting units (20 and 50) are transmitted to the terminal units (40 and 70) by the relay units (30A, 30B, 60A through 60C), and when the terminal units (40 and 70) receive the ultrasonic waves, the ultrasonic waves are returned from the terminal units (40 and 70), relayed by the relay units (30A, 30B, 60A through 60C), and transmitted to the detecting units (20 and 50). Thus, it is judged whether there is a break in the rails (11, 11A and 11B), based on the ultrasonic wave reception state in the detecting units (20 and 50).

Abstract: The present invention relates to a z-axial solid-state gyroscope. Its main configuration is manufactured with a conductive material and includes two sets of a proof mass and two driver bodies suspended between two plates by an elastic beam assembly. Both surfaces of the driver bodies and the proof masses respectively include a number of grooves respectively perpendicular to a first axis and a second axis. The surfaces of the driver bodies and the proof masses and the corresponding stripe electrodes of the plates thereof are respectively formed a driving capacitors and a sensing capacitors. The driving capacitor drives the proof masses to vibrate in the opposite direction along the first axis. If a z-axial angular velocity input, a Coriolis force makes the two masses vibrate in the opposite direction along the second axis. If a first axial acceleration input, a specific force makes the two masses move in the same direction along the first axis.

Abstract: A suspension diaphragm (16) is configured to support a precision transducer (14) within a container (12). The suspension diaphragm (16) is buttressed by an underlying complaint preform (152) and an annular hybrid support (16B) disposed along the periphery of an opening of the container (12). The transducer (14) is affixed to the suspension diaphragm (16) using the compliant preform (152) and rigid epoxy in the securing channels (120). The annular hybrid support (16B) is affixed to the exterior of the container (12).

Abstract: A sensor includes a housing and a magnetic fluid within the housing that incompletely fills the housing. An inertial body is in contact with the magnetic fluid. Displacement of the inertial body relative to the magnetic fluid is indicative of acceleration on the housing. The acceleration includes linear and/or angular acceleration. The inertial body can be an air bubble, or a dissimilar liquid. A plurality of magnets are mounted on the housing, wherein the magnetic fluid is positioned in droplets between the magnets and the inertial body. The magnetic fluid can be a single droplet between each magnet and the inertial body, or multiple droplets between each magnet and the inertial body. The remaining volume in the housing can be filled with a non-magnetic fluid.

Abstract: Inertial measurement system and method in which a base is rotated about an input axis in accordance with a rotation to be measured, rotation about the input axis is sensed with one or more angular rate sensors, fixed bias offset is cancelled by dithering the sensors about an axis perpendicular to their sensing axes to vary the orientation of the sensing axes relative to the base in an oscillatory manner, and signals from the sensors are demodulated at the dithering frequency.

Abstract: In a piezoelectric element 20, a first electrode layer 2 made of an alloy of at least one metal selected from the group consisting of cobalt, nickel, iron, manganese and copper and a noble metal is formed on a silicon substrate 1, and a piezoelectric layer 3 made of a rhombohedral or tetragonal perovskite oxide (e.g., PZT) is formed on the first electrode layer 2 so that the piezoelectric layer 3 is preferentially oriented along the (001) plane.

Abstract: A housing for a magnetofluidic sensor where the sensor has a plurality of drive magnet assemblies, magnetic fluid and an inertial body. The housing has a plurality of ports for securing respective drive magnet assemblies, such that a portion of each drive magnet assembly is positioned within the housing proximate the magnetic fluid. Each drive magnet assembly includes a magnetic field source for creating a magnetic field within the magnetic fluid for acting upon the inertial body. Each drive magnet assembly also includes a sensing element for sensing movement of the inertial body within the magnetic fluid.

Abstract: A physical quantity (e.g., acceleration) sensing unit is provided. In this unit, a capacitive sensor has first and second fixed electrodes and a physical-quantity-sensitive movable electrode disposed between the first and second fixed electrodes. An adjusting circuit first adjusts a first bias voltage applied between the first fixed electrode and the movable electrode and a second voltage applied between the movable electrode and the second fixed electrode so that the movable electrode is brought into contact with either the first or second fixed electrode. The adjusting circuit then adjusts the first and second bias voltages to return the movable electrode to its original position. A detecting circuit detects an output on a capacitance relationship among the first and second fixed electrodes and the movable electrode. The output is subjected to determination of whether or not the output is out of order, when tested.

Abstract: A high-reliability complex sensor is protected against vibration and electromagnetic wave noise from outside. A shield case is provided with a power conjunction terminal, GND conjunction terminal, angular velocity conjunction terminal, X axis acceleration conjunction terminal and Y axis acceleration conjunction terminal. Both a power supply terminal of an angular velocity detection device and a power supply terminal of an acceleration detection device are electrically connected with a power connector terminal of a protection case, via the power conjunction terminal of the shield case. Both a GND terminal of the angular velocity detection device and a GND terminal of the acceleration detection device are electrically connected with a GND connector terminal of the protection case, via the GND conjunction terminal of the shield case. A circuit board is contained completely within the shield case.

Abstract: A Micro Electro-Mechanical System (MEMS) acceleration sensing device formed of a silicon substrate having a substantially planar surface; a pendulous sensing element having a substantially planar surface suspended in close proximity to the substrate planar surface; a flexure suspending the sensing element for motion relative to the substrate planar surface, the flexure having a both static geometric centerline and a dynamic centerline that is offset from the static geometric centerline; and a metal electrode positioned on the substrate surface for forming a capacitor with the pendulous sensing element, the metal electrode being positioned as a function of the dynamic centerline of the flexure.

Abstract: An accelerometer includes an inertial body; a magnetized fluid holding the inertial body in suspension; and a plurality of capacitive elements, each forming a capacitor with the inertial body. A displacement of the inertial body produces a change of capacitance of the capacitive elements that is indicative of acceleration. The capacitive elements include at least two capacitive elements per side of the accelerometer. A housing encloses the inertial body and the magnetized fluid, and the plurality of capacitive elements are mounted on the housing. The housing can be cylindrical shaped, rectangular shaped and tetrahedral-shaped. The inertial body can include a disk-shaped magnet, an annular-shaped magnet, or be non-magnetic, or be weakly magnetic. The acceleration can be linear acceleration, angular acceleration, or three components of angular acceleration and three components of linear acceleration. A plurality of magnets magnetize the magnetic fluid.

Abstract: A velocity measuring device is mounted to a support, optionally a wearable support such as a glove, watch, wrist or arm band, or the like. Alternatively, the support is a sports club or removably attaches to a sports club. The velocity measuring device includes a power supply, a velocimeter or accelerometer, and an output device for visually, aurally, or electrically outputting the measured velocity.

Abstract: An exemplary embodiment of the present invention creates a micromechanical rotational rate sensor having a first Coriolis mass element and a second Coriolis mass element which may be situated over a surface of a substrate. An exemplary embodiment of a micromechanical rotational rate sensor may have an activating device by which the first Coriolis mass element and the second Coriolis mass element are able to have vibrations activated along a first axis. An exemplary embodiment of a micromechanical rotational rate sensor may have a detection device by which deflections of the first Coriolis mass elements and of the second Coriolis element are able to be detected along a second axis, which is perpendicular to the first axis, on the basis of a correspondingly acting Coriolis force. The first axis and second axis may run parallel to the surface of the substrate. The detecting device may have a first detection mass device and a second detection mass device.

Abstract: In an implementation in rate gyro mode, the method includes exciting the vibrating member with a combination of control signals including an amplitude control signal at a frequency twice the resonant frequency, and a quadrature control signal at DC. In free gyro mode, the method includes the steps of applying a combination of signals to common electrodes 5 and of applying the combination in alternation to main electrodes 5.1 and 5.2 and to auxiliary electrodes 7.1 and 7.2 interleaved between the main electrodes.

Abstract: In an implementation in rate gyro mode, the method includes exciting the vibrating member with a combination of control signals including an amplitude control signal at a frequency twice the resonant frequency, and a quadrature control signal at DC. In free gyro mode, the method includes the steps of applying a combination of signals to common electrodes 5 and of applying the combination in alternation to main electrodes 5.1 and 5.2 and to auxiliary electrodes 7.1 and 7.2 interleaved between the main electrodes.

Abstract: Techniques for measuring a density of a liquid within a fluid that includes both a liquid and a gas are described. A pressure of the fluid oscillates according to a time-varying function, which causes a density of the fluid also to oscillate according to the same time-varying function. A resulting pressure signal and density signal are analyzed to extract at least a first and second pressure value and at least a first and second density value, where the first pressure and density values occur at a first time, and the second pressure and density values occur at a second time. Then, the liquid density is calculated from the first and second pressure and density values. As a result, the liquid density may be calculated quickly and easily, with a minimum of effort on the part of an operator, and without requiring disruption of other measurement processes associated with the flowtube.

Abstract: A semiconductor device includes gaps formed in a semiconductor substrate to provide an inner portion movable in x and y directions. Drive electrodes vibrate the inner portion in the x direction, and detection electrodes detect movement in the y direction generated when an angular velocity is applied thereto. Monitor electrodes generate monitor signals for monitoring movement of the inner portion in the x direction. Shield wires are provided between the drive and detection electrodes and the monitor electrodes to suppress capacitive coupling. Dummy electrodes adjacent to the output electrodes and capacitively coupled to the drive electrodes generate a dummy signal. Dummy signal wires are respectively connected to the dummy electrodes and to the circuit substrate. The dummy signal includes an induced component of a periodical signal and is supplied to the circuit substrate to cancel another induced component of the periodical signal in the drive and monitor signals.

Abstract: In a method for detecting rotational speed of an internal combustion engine (1), a sector wheel (4) which is driven by the internal combustion engine (1) is scanned, the run of a specific segment of the sector wheel is detected, the duration of said segment-run is measured and a rotational speed value is determined therefrom, the duration of the run a specific segment is re-measured, a relative variation between two consecutive segment-runs is determined and the rotational speed value is determined therefrom.